Storm Prediction Center Mesoscale Discussion 270

   Mesoscale Discussion 0270
   NWS Storm Prediction Center Norman OK
   1255 PM CDT Mon Mar 18 2024

   Areas affected...Portions of the central and eastern Florida
   Peninsula

   Concerning...Severe potential...Watch unlikely 

   Valid 181755Z - 182030Z

   Probability of Watch Issuance...20 percent

   SUMMARY...Strong to severe storm potential will gradually increase
   through the afternoon across portions of the central and eastern FL
   Peninsula. Primary concerns are isolated large hail and locally
   damaging gusts.

   DISCUSSION...Latest day cloud phase satellite imagery indicates a
   deepening boundary-layer cumulus field developing along/ahead of a
   diffuse ENE/WSW-oriented cold front draped across central FL this
   afternoon. Isolated convection is beginning to develop within this
   cumulus field, as the associated frontal ascent intersects
   steepening boundary-layer lapse rates and rich moisture (upper
   60s/lower 70s surface dewpoints). During the next few hours, the
   continued ascent and destabilization should support isolated to
   widely scattered thunderstorms, which will generally spread
   east-southeastward along the front, with additional isolated
   development possible along differential heating boundaries into
   southern FL. 

   The 15Z XMR sounding and more recent ACARS and VWP data are sampling
   50-60 kt midlevel west-southwesterly flow, which is contributing to
   a long/mostly straight hodograph (40-50 kt of effective shear).
   This, combined with the continued boundary-layer destabilization
   beneath relatively steep midlevel lapse rates, will support
   organized multicells and transient/splitting supercells. As this
   activity spreads eastward into the increasing surface-based
   instability, the risk of isolated large hail up to 1.75 inches and
   locally damaging gusts (potentially near 60 mph) will increase.
   While less likely, a brief tornado cannot be entirely ruled out
   along the east coast, where surface winds are beginning to back,
   yielding modest low-level hodograph curvature/low-level streamwise
   vorticity.

   Given that large-scale forcing for ascent is weak and surface winds
   are veered ahead of the front, the overall coverage of severe storms
   should be limited, and storm intensification may be gradual.
   Therefore, the severe risk appears too isolated for a watch at this
   time.

   ..Weinman/Goss.. 03/18/2024

   ...Please see www.spc.noaa.gov for graphic product...

   ATTN...WFO...MFL...MLB...TBW...JAX...

   LAT...LON   26727995 26228000 26078019 26198045 26798095 27368174
               27438212 27748246 28148253 28528245 28938224 29328165
               29438126 29408095 28998062 28378030 27228003 26727995